Modern semiconductors have become extremely complex and are highly susceptible to damage from external influences, such as contaminants, mechanical shock, electrostatic discharges and physical contact. Accordingly, various types of carriers have been developed to protect the delicate semi-conductors as they are transported between the many process steps needed for production of a finished electronic circuit or device. Various types of carriers have been developed for this purpose and are known in the art, including carrier tapes that are designed to carry the components in a continuous fashion.
Carrier tapes are also widely used for a variety of devices other than semi-conductors. Such other devices include connectors, sockets, electromechanical components, and passive/discrete components. Packaging devices in carrier tape enables automatic loading and unloading of devices into and out of the carrier tape and provides an efficient and compact means to ship product from one location to another.
One popular type of carrier tape includes a continuous strip of thermoplastic material with a series of pockets embossed therein, each pocket for containing one component. The margins of the strip typically have sprocket holes so that the tape can be moved between process steps by a conveyor system using sprockets adapted to engage the sprocket holes. Typically, a cover tape is placed over the pockets so as to retain the components.
Since robotic tools are often used in device manufacturing processes to remove components from the pockets in carrier tape, there is a need for great precision in component positioning. Consequently, pockets must be precisely spaced and indexed with the sprocket holes to ensure an accurately repeatable, predictable position for the component. Also, the component positioning surfaces within each pocket must be uniform and free from distortion that may cause variations in component positioning.
Previously, inefficiencies have been associated with the use of embossed carrier tape that have tended to reduce its use. Typically, in previous processes, carrier tape is embossed in one process and is wound on large rolls for transport to another location where the components are loaded in the pockets and cover tape is applied. In addition to inefficiency resulting from the extra transport step itself, the rolls of carrier tape with formed pockets are much bulkier than flat rolls of carrier tape stock, leading to further transport inefficiency. Also, the formed pockets are subject to crushing and other damage in handling.
Previous embossed carrier tape manufacturing processes have proven difficult to integrate with component filling and sealing processes. Typically, in these previous processes, entire sections of tape are heated prior to embossing the pockets. Consequently, it is difficult to stop and start the tape manufacturing process as may be needed to accommodate a differing input rate for a pocket filling apparatus, without causing heat damage to a section of the tape or introducing an unacceptable delay while the heater is shut down and restarted. A damaged section of tape in a roll is unacceptable and results in rejection of the entire roll.
A need exists in the industry for a carrier tape manufacturing apparatus that is easily integratable with filling and sealing processes.